1. Field of the Invention
This invention relates generally to measurement devices, and more specifically to an improved flow meter device for measurement of two-phase or multi-phase flow mixtures.
2. Description of the Prior Art
The present invention relates to devices for the measurement of a two-phase or multi-phase flow mixture such as a fluid and a solid; or a vapor, liquid and a solid; or as vapor and liquids flowing within a conduit. Such devices are highly beneficial in the measurement of coal slurry; geothermal steam; noncondensable gas and brine; oil, gas and water; as well as other mixtures containing two or more components. The measurement of two or more phases flowing in a conduit is important or even necessary in the production or processing of fluids. In the oil and gas industry, the production of oil and/or gas is oftentimes accompanied by water. Separation facilities required to isolate each of the phases for individual measurement are expensive, complex and bulky. The present technique temporarily separates the phases within the pipeline for pseudo measurements without the need for permanent separation. Computational techniques can resolve the mixture into individual components. It reduces process complexities and saves valuable space, especially in areas such as offshore platforms.
Prior art patents such as those to Furmaga (U.S. Pat. No. 4,429,581) utilize a complex array of piping and instrumentation including the use of a separator. The patents to Pitts (U.S. Pat. Nos. 4,144,754 and 4,282,760) utilize a rectangular full circle loop whereby a centrifugal force is measured and a density is measured. A volumetric measurement can be utilized by means of a positive displacement flow meter. The patent to Arnold et al. (U.S. Pat. No. 4,272,982) measures density within a built-in positive displacement flow meter. The patent to Sabin (U.S. Pat. No. 4,604,902) utilizes a venturi coupled with an array of temperature differential flow meters. There are other techniques used to measure multi-phase flow, but most utilize mixers to blend the total flow prior to measurement. All of these prior art devices are very different from the present device.
Applicants aforementioned co-pending application stresses the measurement of two-phase flow. However, the measurement of two or more phases can be readily accomplished using the basic techniques established, with additional measurements, and/or modifications, as described herein.